Use of a lubricating grease composition having a high upper use temperature

ABSTRACT

A lubricant grease composition is disclosed, the lubricant grease composition including a base oil and a thickener. The thickener includes an aluminum-based complex soap and a polyurea thickener, wherein the lubricant grease is configured for lubrication of surfaces of components in which an upper use temperature of the lubricant grease composition is at least 90° C.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Phase application under 35 U.S.C. §371 of International Application No. PCT/EP2020/080748, filed on Nov. 3,2020, and claims benefit to German Patent Application No. DE102019134330.5, filed on Dec. 13, 2019. The International Applicationwas published in German on Jun. 17, 2021 as WO 2021/115685 A1 under PCTArticle 21(2).

FIELD

The present invention relates to the use of a lubricant greasecomposition for lubrication of surfaces in applications in which a highupper use temperature is required, and especially in the automotiveindustry.

BACKGROUND

In the past, lubricant greases were used predominantly for purelymetallic components. In order to meet constantly rising demands on lowerweight and lower costs, for example in the automotive industry, however,there is increasing use of plastic-containing components. For thatreason, there is a rise in demand for lubricant greases matched tolubrication of plastic-containing friction partners and/or to acombination of metallic and plastic-containing friction partners.

An important field of use for the lubrication of plastic surfaces is thelubrication of friction partners in actuators. This is firstly becausethey are taking on an increasingly important role in measurement,control and regulation technology, for example in the automotiveindustry, and secondly because they generally have at least partlyplastic-containing friction partners. But plastic-containing frictionpartners make different demands on lubricant greases than purelymetallic components, and so the lubricant greases customarily used theregenerally do not give satisfactory results, for example with regard tocoefficients of friction or service life.

One way of adjusting the properties of the lubricant greases is bysuitable selection of the thickeners. For particular applications,aluminum complex soaps have been found to be suitable thickeners. Forinstance, aluminum complex soaps as thickeners for lubricant greasecompositions have long been known and are described in many literaturereferences, for example in J. L. Dreher, T. H. Koundakijan and C. F.“Manufacture and Properties of Aluminum Complex Greases”, NLGISpokesman, 107-113,1965; H. W. Kruschwitz “The Development ofFormulations for Aluminum Complex Thickener Systems” NLGI Spokesman,51-59,1976; H. W. Kruschwitz “The Manufacture and Uses of AluminumComplex Greases” NLGI National Meeting Preprints 1985.

Nevertheless, the global market for greases is dominated by conventionalsimple lithium soaps as thickener, followed by complex lithium soaps andsimple calcium soaps. Specifically in the automotive industry, where ahigh demand on the temperature use range is generally made (at least−40° C. to +120° C.), aluminum complex soaps are barely present. This isall the more astonishing since the use of aluminum complex soaps bringsmultiple advantages. Compared to simple and complex lithium soaps, oneadvantage here would be the better availability of the aluminum source.Specifically in the age of electromobility, the cost of lithiumhydroxide has drastically increased in the last few years, and it is notpossible to clearly foresee how the availability and price will develop.Furthermore, aluminum complex soaps have good water resistance,pumpability, good low-temperature characteristics and high materialcompatibility.

A further advantage of aluminum complex soaps is that they are capable,on account of their high shear instability, of lowering the dynamicviscosity of the lubricant. As a result, they enable the use of baseoils having higher viscosities, which is advantageous especially in thecase of metal/plastic friction partners. As a result of the higherlubricant film obtained thereby between the friction partners, it isthus possible to reduce wear over the lifetime. Furthermore, an elevatedbase oil viscosity is advantageous for noise vibration hardness (NVH)characteristics in the component.

The disadvantage of aluminum complex soaps, which is certainly also areason why they have not found wide use in the automotive industry, isthat although aluminum complex soaps do have a high dripping point(>220° C.), this cannot be equated with the upper use temperature.Aluminum complex soaps, depending on their consistency index (NLGI),become fluid with time at temperatures above 90° C., and are thus nolonger available to the friction site to be lubricated and therefore donot meet the demand from the automotive industry for a high upper usetemperature, which should preferably be at least 120° C.

Accordingly, for example, EP2077318 (Al) describes an aluminumcomplex-free lubricant grease composition for use of plastic-containingfriction partners in automobiles. The lubricant grease compositioncontains a base oil selected from at least one synthetic hydrocarbonoil, a synthetic ester-based oil and a synthetic ether-based oil, and athickener selected from at least one lithium-based soap, a lithium-basedcomplex soap and a urea-based compound.

It would therefore be desirable to obtain a lubricant grease compositionbased on an aluminum complex thickener which is suitable for lubricationof the surfaces of plastic-containing friction partners or of acombination of metallic and plastic-containing friction partners andwhich has satisfactory thermal stability in the form of an upper usetemperature of preferably more than 90° C. and especially more than 120°C.

SUMMARY

In an embodiment, the present disclosure provides a lubricant greasecomposition comprising a base oil and a thickener including analuminum-based complex soap and a polyurea thickener, wherein thelubricant grease is configured for lubrication of surfaces of componentsin which an upper use temperature of the lubricant grease composition isat least 90° C.

Figure

DETAILED DESCRIPTION

This object is achieved in accordance with the invention by the use of alubricant grease composition comprising

-   -   a base oil,    -   a thickener comprising an aluminum-based complex soap and a        polyurea thickener, for lubrication of the surfaces of        components in applications in which an upper use temperature of        the lubricant grease composition of at least 90° C., for example        90° C. to 180° C. and/or 90° C. to 160° C. and/or 90° C. to 150°        C., preferably at least 100° C., for example 100° C. to 180° C.        and/or 100° C. to 160° C. and/or 100° C. to 150° C., more        preferably 110° C. to 180° C. and/or 110° C. to 170° C. and/or        110° C. to 160° C. and/or 110° C. to 150° C., is required.

It has been found in accordance with the invention that, surprisingly,the use of a thickener comprising an aluminum-based complex soap incombination with a polyurea thickener makes it possible to obtain alubricant grease composition of excellent suitability for lubrication ofthe surfaces of components in applications in which a high upper usetemperature of the lubricant grease composition is required. Thus, thelubricant grease composition is of excellent suitability forapplications in the automotive sector, since the use temperaturesrequired in the automotive sector, which are typically in the range from−40° C. to +120° C., can be achieved without difficulty. Examples ofapplications in which an upper use temperature of the lubricant greasecomposition of at least 90° C. is required is the lubrication of balljoints, spur gears, worm gears and planetary gears and actuators ofbrush-operated or brushless DC motors (DC, BLDC motors) and/or AC motors(AC, BLAC motors).

The lubricant grease composition used in accordance with the inventionpreferably has an upper use temperature of at least 90° C., for example90° C. to 180° C. and/or 90° C. to 160° C. and/or 90° C. to 150° C.,preferably at least 100° C., for example 100° C. to 180° C. and/or 100°C. to 160° C. and/or 100° C. to 150° C., more preferably 110° C. to 180°C. and/or 110° C. to 170° C. and/or 110° C. to 160° C. and/or 110° C. to150° C.

An upper use temperature of the lubricant grease composition isunderstood to mean the highest temperature at which the lubricant greasecomposition can be used without losing its use capability. The upper usetemperature can be determined in accordance with the invention bymeasuring oil separation at various temperatures. According to theinvention, the upper use temperature of the lubricant grease compositionis the highest temperature at which the lubricant grease composition hasan oil separation to ASTM D6184-17 (24 h/X° C.) of less than 12% byweight. The lubricant grease composition preferably has an oilseparation to ASTM D6184-17 (24 h/100° C.) of less than 12% by weight,more preferably of less than 10% by weight and especially less than 6%by weight. Likewise preferably, the lubricant grease composition has anoil separation to ASTM D6184-17 (24 h/100° C., then 24 h/110° C.) ofless than 16% by weight, more preferably of less than 14% by weight andespecially less than 13% by weight. Likewise preferably, the lubricantgrease composition has an oil separation to ASTM D6184-17 (24 h/100° C.,then 24 h/110° C., then 24 h/120° C.) of less than 20% by weight, morepreferably of less than 15% by weight and especially less than 12% byweight.

In an embodiment of the invention, the lubricant grease composition hasa use temperature range from −60° C. to +180° C. and/or of −50° C. to+160° C., and/or of −40° C. to +150° C. and/or of −40° C. to +140° C.and/or of −40° C. to +120° C. A use temperature range of the lubricantgrease composition is understood to mean the temperature range in whichthe lubricant grease composition can be used without losing its usecapability. For instance, according to the invention, a lubricant greasecomposition at its use temperature has an oil separation to ASTMD6184-17 (24 h/X° C.) of less than 12% by weight. In addition, alubricant grease composition at its use temperature has a flow pressure(DIN 51805-2:2016-09) of not more than 1400 mbar.

Nevertheless, the lubricant grease composition can also be used attemperatures higher or lower than the abovementioned temperatures,provided that these temperatures occur only for a short period of time,for example less than 10 minutes.

The invention further provides for the use of a lubricant greasecomposition comprising

-   -   a base oil,    -   a thickener comprising an aluminum-based complex soap and a        polyurea thickener,        for lubrication of the surfaces of components at temperatures        that are at least inteiu ittently at least 90° C., for example        90° C. to 180° C. and/or 90° C. to 160° C. and/or 90° C. to 150°        C., preferably at least 100° C., for example 100° C. to 180° C.        and/or 100° C. to 160° C. and/or 100° C. to 150° C., more        preferably 110° C. to 180° C. and/or 110° C. to 170° C. and/or        110° C. to 160° C. and/or 110° C. to 150° C.

In an embodiment of the invention, the temperature is maintained for aperiod of at least 10 minutes, more preferably of at least 20 minutes,more preferably of at least 40 minutes and especially of at least 60minutes.

The high thermal stability of the lubricant grease composition wassurprising in that the use of aluminum-based complex soaps, aselucidated above, is known to lead to lubricant greases havingcomparatively low thermal stability of generally below 90° C. Withoutcommitting to any mechanism, it is suspected that a synergism developsbetween aluminum complex soap and polyurea thickener that increases thethermal stability of the aluminum complex soap. This is probably becausethe two thickener components have good mutual miscibility, and hence theresult is a hybrid thickener system. The distinctly higher upper usetemperature of the polyurea thickener has a positive influence on theupper use temperature of the aluminum-based complex soap withoutadversely affecting the general positive properties of thealuminum-based complex soap.

A polyurea thickener is understood to mean a reaction product of adiisocyanate, preferably 2,4- diisocyanatotoluene,2,6-diisocyanatotoluene, 4,4′-dii socyanatodiphenylmethane,2,4′-diisocyanatophenylmethane, 4,4′-diisocyanatodiphenyl,4,4′-diisocyanato-3,3′-dimethylphenyl,4,4′-diisocyanato-3,3′-dimethylphenylmethane, which may be usedindividually or in combination, with an amine of the general formulaR′2-N—R, or a diamine of the general formula R′2-N—R—NR′2 where R is anaryl, alkyl or alkylene radical having 2 to 22 carbon atoms and R′ isidentical or different and is a hydrogen or an alkyl, alkylene or arylradical having 2 to 22 carbon atoms, or with mixtures of amines anddiamines.

The proportion of the polyurea thickener in the lubricant greasecomposition of the invention is preferably 1% by weight to 11% byweight, more preferably from 2% by weight to 10% by weight, andespecially from 3% by weight to 9% by weight, based in each case on thetotal weight of the lubricant grease composition.

According to the invention, it is possible in principle to use a widevariety of different aluminum-based complex soaps that are customarilyused in lubricant grease compositions. In one embodiment of the presentinvention, aluminum-based complex soaps of the

are preferred on account of their good availability. The fatty acidradical R here is preferably an aliphatic hydrocarbyl radical having 4to 28 carbon atoms (R=C₄-C₂₈). Preference is given here to an evennumber of carbon atoms since this occurs in most naturally occurringfatty acids. More preferably, R=C₁₂-C₂₂. Further preferably, the Rradicals are derived from fatty acids selected from the group consistingof lauric acid, palmitic acid, mytistic acid, stearic acid and mixturesthereof.

Aluminum-based complex soaps as shown in formula 1 are aluminumcarboxylate compounds that can be prepared by a reaction of a fattyacid, an aromatic carboxylic acid and an aluminum-alcohol derivative.Commercially used aluminum alkoxides are aluminum isopropoxide ortrioxyaluminum triisopropoxide. A simple route to preparation of theaforementioned aluminum-based complex soaps comprises the reactionbetween a trioxyaluminum triisopropoxide (Al trimer for short), a fattyacid and a benzoic acid:

Alternatively, it is also possible to convert an intermediate, forexample polyoxyaluminum stearate, to the corresponding complex soap. Ingrease production, this obviates the need to release a low molecularweight alcohol, for example isopropyl alcohol.

What is advantageous about the use of the aluminum-based complex soapsas thickener, as elucidated above, is that they combine goodavailability with low cost.

Furthermore, aluminum complex soaps have good water resistance,pumpability, good low-temperature characteristics and high materialcompatibility.

The proportion of the aluminum-based complex soap in the lubricantgrease composition of the invention is preferably from 1% by weight to11% by weight, more preferably from 2% by weight to 10% by weight andespecially from 3% by weight to 9% by weight, based in each case on thetotal weight of the lubricant grease composition.

In an embodiment of the invention, the proportion of aluminum-basedcomplex soap and polyurea thickener together is from 2% by weight to 22%by weight, more preferably from 4% by weight to 20% by weight andespecially from 6% by weight to 18% by weight, based in each case on thetotal weight of the lubricant grease composition.

In some embodiments the invention encompasses the use of the lubricantgrease composition for lubrication of the surfaces of plastic-containingfriction partners or of a combination of metallic and plastic-containingfriction partners and especially of friction partners of theaforementioned type in actuators, especially in the automotive sector.

Suitable base oils are customary lubricant oils that are liquid at roomtemperature (20° C.). The base oil preferably has a kinematic viscosityof 18 mm²/s to 20 000 mm²/s, especially from 30 mm²/s to 400 mm²/s, at40° C. Base oils are distinguished between mineral oils and syntheticoils. A base oil is understood to mean the customary base fluids usedfor the production of lubricants, especially oils that are assigned togroups I, II, II+, III, IV or V according to the classification of theAmerican Petroleum Institute (API) [NLGI Spokesman, N. Samman, volume70, number 11, p. 14 et seq.]. Mineral oils are classified by API group.API Group I are mineral oils consisting, for example, of naphthenic orparaffinic oils. If these mineral oils, by comparison with API Group Ioils, have been chemically modified, have a low aromatics level and lowsulfur level and have a low proportion of saturated compounds and henceimproved viscosity/temperature characteristics, the oils are classifiedas API Group II and III. API Group III also includes what are calledgas-to-liquid oils that are produced not from the refining of crude oilbut by the chemical conversion of natural gas.

Synthetic oils include polyethers, esters, polyesters, preferablypolyalphaolefins, especially metallocene polyalphaolefins, polyethers,perfluoropolyalkyl ethers (PFPAE), alkylated naphthalenes, silicone oilsand alkylaromatics and mixtures thereof. The polyether compound may havefree hydroxyl groups, but may also have been fully etherified or endgroup-esterified and/or have been prepared from a starter compoundhaving one or more hydroxyl and/or carboxyl groups (—COOH). Alsopossible are polyphenol ethers, optionally alkylated, as the solecomponents or even better as mixed components.

Suitably usable are esters of an aromatic and/or aliphatic di-, tri- ortetracarboxylic acid with one or a mixture of C₇ to C₂₂ alcohols, estersof trimethylolpropane, pentaerythritol or dipentaerythritol withaliphatic C₇ to C₂₂ carboxylic acids, esters of C₁₈ dimer acids with C₇to C₂₂ alcohols, complex esters, as individual components or in anymixture.

Likewise suitable are silicone oils, native oils and derivatives ofnative oils.

Base oils particularly preferred in accordance with the invention arepolyalphaolefins, especially metallocene polyalphaolefins, andnaphthenic mineral oils according to the API Group I classification.

In an embodiment of the invention, the proportion of the base oil in thelubricant grease composition of the invention is from 55% by weight to90% by weight, more preferably from 60% by weight to 95% by weight, andespecially from 68% by weight to 92% by weight, based in each case onthe total weight of the lubricant grease composition.

As well as base oil(s) and thickener(s), the composition of theinvention may also contain further additives, for example antioxidants,anticorrosives, lubricity improvers, high-pressure and antiwearadditives, metal deactivators, viscosity and friction improvers, dyes,friction reducers.

The addition of antioxidants can reduce or even prevent the oxidation ofthe lubricant grease composition of the invention, especially on usethereof. Oxidation can give rise to unwanted free radicals, resulting inan increased level of occurrence of break down reactions of thelubricant. The addition of antioxidants stabilizes the lubricant greasecomposition.

Antioxidants that are particularly suitable in accordance with theinvention are the following compounds: styrenized diphenylamines,diaromatic amines, phenolic resins, thiophenolic resins, phosphites,butylated hydroxytoluene, butylated hydroxyanisole,phenyl-alpha-naphthylamine, phenyl-beta-naphthylamine,octylated/butylated diphenylamine, di-alpha-tocopherol,di-tert-butylphenyl, benzenepropanoic acid, sulfur-containing phenolcompounds and mixtures of these components.

In addition, the lubricant grease composition may contain furtheradditives, especially anticorrosion additives, metal deactivators orion-complexing agents. These include triazoles, imidazolines,N-methylglycine (sarcosine), benzotriazole derivatives,N,N-bis(2-ethylhexyl)-ar-methyl-1H-benzotriazole-1-methanamine;n-methyl-N-(1-oxo-9-octadecenyl)-glycine, mixtures of phosphoric acidand mono- and diisooctyl esters reacted with (C₁₁-14)-alkylamines,mixtures of phosphoric acid and mono- and diisooctyl esters reacted withtert-alkylamine and primary (C₁₂-14)-amines, dodecanoic acid, triphenylphosphorothionate and amine phosphates. Commercially available additivesare as follows: IRGAMET® 39, IRGACOR® DSS G, Amin 0; SARKOSYL® 0 (Ciba),COBRATEC® 122, CUVAN® 303, VANLUBE®9123, CI-426, CI-426EP, CI-429 andCI-498.

Further conceivable antiwear additives are amines, amine phosphates,phosphates, thiophosphates, phosphorothionates and mixtures of thesecomponents. The commercially available antiwear additives includeIRGALUBE® TPPT, IRGALUBE® 232, IRGALUBE® 349, IRGALUBE®211 and ADDITIN®RC3760 Liq 3960, FIRC—SHUN® FG 1505 and FG 1506, NA-LUBE® KR-015FG,LUBEBOND®, FLUORO® FG, SYNALOX®40-D, ACHESON® FGA 1820 and ACHESON® FGA1810.

The proportion of the further additives is preferably from 1% by weightto 30% by weight, more preferably from 1.5% by weight to 25% by weight,and especially from 2% by weight to 20% by weight, in each case based onthe total weight of the lubricant grease composition.

In addition, the lubricant grease composition may contain solidlubricants such as PTFE, boron nitride, polymer powders, for examplePTFE, polyamides or polyimides, pyrophosphate, metal oxides, for examplezinc oxide or magnesium oxide, metal sulfides, for example zinc sulfide,molybdenum sulfide, tungsten sulfide or tin sulfide, pyrophosphates,thiosulfates, magnesium carbonate, calcium carbonate, calcium stearate,carbon polymorphs, for example carbon black, graphite, graphene,nanotubes, fullerenes, SiO2 polymorphs, melanin cyanurate, or a mixturethereof.

The proportion of the solid lubricants is preferably from 1% by weightto 30% by weight, more preferably from 1.5% by weight to 25% by weight,and especially from 2% by weight to 20% by weight, based in each case onthe total weight of the lubricant grease composition.

Further preferably, the lubricant grease composition has a workedpenetration, determined to DIN ISO 2137:2016-12, of 265 to 385 0.1 mm.According to the National Lubricating Grease Institute (NLGI) scale,this corresponds to a consistency class no. 0-2 as per DIN51818:1981-12.

In an embodiment of the invention, the lubricant grease composition hasthe following composition:

-   -   55°/h to 96% by weight of base oil,    -   1% to 11% by weight of polyurea thickener,    -   1% to 11% by weight of aluminum-based complex soap,    -   1% to 30% by weight of additives,    -   1% / to 30% by weight of solid lubricants.

The invention is elucidated in detail hereinafter with reference tovarious examples.

Production of a lubricant grease composition of the invention:

A standard production method for lubricant greases is used. Heatedreactors are used, which may also be designed as an autoclave or vacuumreactor. If required, the resultant grease can be homogenized, filteredand/or devolatilized.

Production method A: Formation of a lubricant grease composition of theinvention by separate production of an aluminum-based complex soap (basegrease A) and a polyurea thickener (base grease B—H) with subsequentmixing and additization

Base Grease a (Aluminum-Based Complex Soap):

A heatable reaction vessel equipped with a stirrer system suitable forthe production of lubricant greases is initially charged with the baseoil or a portion of the base oil or oil mixture. The aluminum-basedcomplex soap is produced therein by reaction of polyoxyaluminum stearatewith benzoic acid and stearic acid. Subsequently, the reaction mixtureis heated, wherein peak temperatures up to 210° C. may occur, in orderto drive out the water and to melt the thickener. The subsequent coolingphase determines the morphology of the thickener. It is possible here touse residual base oil for controlled adjustment of the consistency.

Base Greases B—H (Polyurea Thickener):

A heatable reaction vessel equipped with a stirrer system suitable forthe production of lubricant greases is initially charged with the baseoil or a portion of the base oil or oil mixture. Subsequently, theisocyanate component(s) is/are added and heated to 60° C. whilestirring. In a separate reaction vessel, a portion of the base oil ismixed with the amine component(s) at 60° C. until the solution ishomogeneous. The amine solution is added while stirring the isocyanatesolution and heated up to 200° C. The subsequent cooling phasedetermines the morphology of the thickener. It is possible here to useresidual base oil for controlled adjustment of the consistency.

Base grease A and polyurea grease (base grease B—H) are mixed in aheatable reaction vessel equipped with a stirrer system suitable for theproduction of lubricant greases. The additives are added while stirringover and above 120° C. Once the desired consistency has been attained,the product is homogenized, and optionally filtered and devolatilized.

Production method B: Formation of the lubricant grease composition bysequential production of an aluminum-based complex soap and a polyureathickener in the base oil with subsequent addition of the additives. Aheatable reaction vessel equipped with a stirrer system suitable for theproduction of lubricant greases is initially charged with the base oilor a portion of the base oil or oil mixture. The aluminum-based complexsoap is produced therein by reaction of polyoxyaluminum stearate withbenzoic acid and stearic acid. Subsequently, the reaction mixture isheated, wherein peak temperatures up to 210° C. may occur, in order todrive out the water and to melt the thickener. Subsequently, the brew iscooled down to 60° C., and the isocyanate component(s) is/are added andmelted while stirring. In a separate reaction vessel, a portion of thebase oil is mixed with the amine component(s) at 60° C. until thesolution is homogeneous. The amine solution is added while stirring theisocyanate solution and heated up to 200° C. The subsequent coolingphase determines the morphology of the thickener. It is possible here touse residual base oil for controlled adjustment of the consistency. Theadditives are added while stirring over and above 120° C. Once thedesired consistency has been attained, the product is homogenized, andoptionally filtered and devolatilized.

By the above-described process, the lubricant grease compositions shownin table 1 and table 2 (base greases A 1-2/base greases B—H/hybrids1-15) are produced.

A comparison of production methods A and B is shown in table 3. Smalldifference in the penetration values shows that both production methodsare suitable for production of a corresponding hybrid grease.

Penetration is determined to DIN ISO 2137:2016-12. What is measured isworked penetration after 60 twin strokes.

Oil separation is determined to ASTM D6184-17 with the differencesdescribed below. For table 4, the contact time is different and is 72 h,with, after every 24 h, i) determination of the amount of oil separatedand ii) an increase in the temperature by 10° C. For table 5, thecontact time is 30 h. A separate measurement is effected here at 130° C.and at 150° C.

TABLE 1 Production of base greases A1 A2 B C D E F G H Toluene 2,4-/2,6-X X X diisocyanate Diphenylmethane 4,4′- X X X X X X diisocyanateBenzoic acid X X Cyclohexylamine X X Ethylenediamine X Oleylamine X X XX X PAO X X X X X X X X Polyoxyaluminum stearate X X p-Phenetidine X Xn-Octylamine X X X X X X Stearic acid X X Thickener content [% by 15 1215 13 15 15 15 15 15 wt.] Penetration ( 1/10 mm) 330 346 285 186 185 198234 340

TABLE 2 Production of hybrid greases AK component PU component PAOPenetration [% by wt.] [% by wt.] [% by wt.] [ 1/10 mm] Hybrid 1 50.0/A2 50.0/E  — 339 Hybrid 2 48.5/A 2 24.0/G 27.5 336 Hybrid 3 47.0/A 223.5/C 29.0 343 Hybrid 4 53.0/A 2 26.5/H 20.0 362 Hybrid 5 62.5/A 232.5/B  5.0 337 Hybrid 6 62.5/A 2 32.5/H  5.0 349 Hybrid 7 73.5/A 2 6.5/F 20.0 349 Hybrid 8 66.5/A 2 13.5/F  20.0 346 Hybrid 9 53.5/A 226.5/F  20.0 337 Hybrid 10 40.0/A 1 40.0/G 20.0 330 Hybrid 11 37.5/A 137.5/C 25.0 330 Hybrid 12 50.0/A 1 50.0/H — 361 Hybrid 13 50.0/A 150.0/B — 342 Hybrid 14 35.0/A 1 35.0/F  30.0 320 Hybrid 15 32.5/A 132.5/D 35.0 325

TABLE 3 Comparison of production methods A/B using two hybrid greaseswith different thickener contents 1-1 1-2 2-1 2-2 3-1 3-2 4-1 4-2Diphenylmethane 4,4′- X X X X X X X X diisocyanate Benzoic acid X X X XX X X X Oleylamine X X X X X X X X PAO X X X X X X X X Polyoxyaluminumstearate X X X X X X X X n-Octylamine X X X X X X X X Stearic acid X X XX X X X X Antioxidant package X X X X X X X X Wear resistance package XX X X X X X X Anticorrosive package X X X X X X X X Viscosity improver XX X X X X X X Friction modifier X X X X X X X X Thickener content of AK[% by 6 6 3 3 4.8 4.8 7.2 7.2 wt.] Thickener content of PU [% by 6 6 3 37.2 7.2 4.8 4.8 wt.] Production method A X X X X Production method B X XX X Penetration ( 1/10 mm) 290  289  370  390  305 288 301 305 5-1 5-26-1 6-2 7-1 8-2 8-1 8-2 Toluene 2,4-/2,6-diisocyanate X X X X X X X XDiphenylmethane 4,4′- X X X X X X X X diisocyanate Benzoic acid X X X XX X X X Oleylamine X X X X X X X X PAO X X X X X X X X Polyoxyaluminumstearate X X X X X X X X p-Phenetidine X X X X X X X X n-Octylamine X XX X X X X X Stearic acid X X X X X X X X Antioxidant package X X X X X XX X Wear resistance package X X X X X X X X Anticorrosive package X X XX X X X X Viscosity improver X X X X X X X X Friction modifier X X X X XX X X Thickener content of AK [% by 6 6 5 5 7.2 7.2 4.8 4.8 wt.]Thickener content of PU [% by 6 6 5 5 4.8 4.8 7.2 7.2 wt.] Productionmethod A X X X X Production method B X X X X Penetration ( 1/10 mm) 335 340  350  350  340 340 310 305

TABLE 4 Determination of oil separation to ASTM D6184-17 after 24 h at100° C., after +24 h at 110° C., and after +24 h at 120° C. 24 h/100° C.24 h/110° C. 24 h/120° C. Specimen [% by wt.] [% by wt.] [% by wt.] Basegrease A 12.76 16.95 21.42 Hybrid 2 5.59 8.74 11.63 Hybrid 3 6.22 8.9211.33 Hybrid 5 4.78 7.35 9.57 Hybrid 6 8.21 10.78 12.67 Hybrid 7 9.6413.29 15.95 Hybrid 8 6.41 9.27 11.86 Hybrid 9 4.84 6.79 8.71

TABLE 5 Determination of oil separation to ASTM D6184-17 at 130° C. and150° C. for 30 h each 30 h/130° C. 30 h/150° C. Grease A 1 12.0 27.0Grease A 2 18.3 — Hybrid 10 7.7 9.4 Hybrid 11 3.4 5.6 Hybrid 12 9.8 8.2Hybrid 13 7.1 10.1 Hybrid 14 9.8 12.0 Hybrid 15 8.6 10.1

The following conclusions can be drawn from the results:

Table 2 shows that the hybrid greases can be produced with a multitudeof combinations between a thickener comprising a complex soap onaluminum and a polyurea thickener. Table 3 shows that both theproduction processes named are suitable for formulating comparablegreases. It is possible here to vary both the content of the thickenerbased on an aluminum complex soap and the content of polyurea thickenerwith respect to one another and also overall.

Table 4 and table 5 show from the comparison of the oil separations thathybrid greases based on a combination of a thickener comprising acomplex soap on aluminum and a polyurea thickener are superior to theconventional aluminum complex soaps at higher use temperatures.

While subject matter of the present disclosure has been illustrated anddescribed in detail in the drawings and foregoing description, suchillustration and description are to be considered illustrative orexemplary and not restrictive. Any statement made herein characterizingthe invention is also to be considered illustrative or exemplary and notrestrictive as the invention is defined by the claims. It will beunderstood that changes and modifications may be made, by those ofordinary skill in the art, within the scope of the following claims,which may include any combination of features from different embodimentsdescribed above.

The terms used in the claims should be construed to have the broadestreasonable interpretation consistent with the foregoing description. Forexample, the use of the article “a” or “the” in introducing an elementshould not be interpreted as being exclusive of a plurality of elements.Likewise, the recitation of “or” should be interpreted as beinginclusive, such that the recitation of “A or B” is not exclusive of “Aand B,” unless it is clear from the context or the foregoing descriptionthat only one of A and B is intended. Further, the recitation of “atleast one of A, B and C” should be interpreted as one or more of a groupof elements consisting of A, B and C, and should not be interpreted asrequiring at least one of each of the listed elements A, B and C,regardless of whether A, B and C are related as categories or otherwise.Moreover, the recitation of “A, B and/or C” or “at least one of A, B orC” should be interpreted as including any singular entity from thelisted elements, e.g., A, any subset from the listed elements, e.g., Aand B, or the entire list of elements A, B and C.

1. A lubricant grease composition comprising: a base oil; and athickener comprising an aluminum-based complex soap and a polyureathickener, wherein the lubricant grease is configured for lubrication ofsurfaces of components in which an upper use temperature of thelubricant grease composition is at least 90° C..
 2. A lubricant greasecomposition comprising: a base oil; and a thickener comprising analuminum-based complex soap and a polyurea thickener, wherein thelubricant grease is configured for lubrication of surfaces of componentsat a temperature that is at least intermittently at least 90° C..
 3. Thelubricant grease claimed in claim 1, wherein the lubricant greasecomposition has a use temperature range of −60° C..
 4. The lubricantgrease claimed in claim 1, wherein a proportion of the polyureathickener in the lubricant grease composition is 1% by weight to 11% byweight, based on the total weight of the lubricant grease composition.5. The lubricant grease claimed in claim 1, wherein the polyureathickener is a reaction product of a diisocyanate selected from thegroup consisting of 2,4- diisocyanatotoluene, 2,6-diisocyanatotoluene,4,4′—diisocyanatodiphenylmethane, 2,4′-diisocyanatophenyl-methane,4,4′-diisocyanatodiphenyl, 4,4′-diisocyanato-3,3′-dimethylphenyl,4,4′-diisocyanato-3,3′-dimethyl-phenylmethane, which may be usedindividually or in combination, with an amine of the general formulaR′2-N—R, or a diamine of the general formula R′2-N—R—NR′2 where R is anaryl, alkyl or alkylene radical having 2 to 22 carbon atoms and R′ isidentical or different and is a hydrogen or an alkyl, alkylene or arylradical, or with mixtures of amines and diamines.
 6. The lubricantgrease claimed in claim 2, wherein the lubricant grease is configuredfor lubrication of surfaces of components when the temperature ismaintained for a period of at least 10 minutes.
 7. The lubricant greaseclaimed in claim 1, wherein the lubricant grease is configured forlubrication of surfaces of plastic-containing friction partners or of acombination of metallic and plastic-containing friction partners inactuators in the automotive sector.
 8. The lubricant grease claimed inclaim 1, wherein the lubricant grease composition has an oil separationaccording to ASTM D 6184-17 (24 h/100° C.) of less than 12% by weightand/or according to ASTM D 6184-17 (24 h/100° C., then 24 h/110° C.) ofless than 16% by weight and/or according to ASTM D 6184-17 (24 h/100°C., then 24 h/110° C., then 24 h/120° C.) of less than 20% by weight. 9.The lubricant grease claimed in claim 1, wherein the aluminum-basedcomplex soap has the formula (A)

where R is an aliphatic hydrocarbyl radical having 4 to 28 carbon atoms.10. The lubricant grease claimed in claim 9, wherein R is derived fromone or more fatty acids selected from the group consisting of lauricacid, palmitic acid, myristic acid, and stearic acid.
 11. The lubricantgrease claimed in claim 1, wherein the proportion of the aluminum-basedcomplex soap in the lubricant grease composition is from 1% by weight to11% by weight based on the total weight of the lubricant greasecomposition.
 12. The lubricant grease claimed in claim 1, wherein theproportion of aluminum-based complex soap and polyurea thickenertogether is from 2% by weight to 22% by weight, based on the totalweight of lubricant grease composition.
 13. The lubricant grease claimedin claim 1, wherein the base oils are polyalphaolefins; or metallocenepolyalphaolefins, and naphthenic mineral oils according to the API GroupI classification.
 14. The lubricant grease claimed in claim 1, whereinthe lubricant grease composition has the following composition: 55% to96% by weight of base oil, 1% to 11% by weight of polyurea thickener, 1%to 11% by weight of aluminum-based complex soap, 1% to 30% by weight ofadditives, and 1% to 30% by weight of solid lubricants.